Short Science, November 24, 2013

PUBLISHED : Sunday, 24 November, 2013, 3:40am
UPDATED : Sunday, 24 November, 2013, 3:40am


Contraceptive pill users at risk of glaucoma

Women who take the contraceptive pill for more than three years are at twice the risk of glaucoma, a common eye disease that can cause blindness if left untreated, US researchers claim. Doctors behind the study urged women at risk to have regular checks for early signs of the disease, which can usually be treated with eye drops if it is caught in time. Glaucoma is caused by a build-up of fluid pressure in the eye, which damages the sensitive optic nerve at the back of the retina. Dr Shan Lin, an ophthalmologist at the University of San Francisco, said long-term use of the contraceptive pill appeared to raise the lifetime risk of glaucoma to around 5 per cent, up from 2.5 per cent in the general population. Guardian


Jaguars turned on by Calvin Klein cologne

Scientists have used Calvin Klein cologne to lure reclusive jaguars. Researchers studying elusive, nocturnal animals often use camera traps, which are triggered when the creature comes close to them. So what's the best way to get these animals to come close enough to get a photo or video? Calvin Klein's Obsession for Men. Miguel Ordenana, a biologist with the Natural History Museum of Los Angeles, who studies the solitary, night-hunting jaguars of Nicaragua, tells the blog that he experimented with other scents, spraying them on a tree branch near the camera trap, before happening on the attraction of the Calvin Klein cologne. "It has civetone and it has vanilla extract," he said. "Civetone is a chemical compound derived from the scent glands of civets [which are native to the Asian and African tropics] and it's one of the world's oldest perfume ingredients." Washington Post


Native Americans may be from west Eurasia

In the "Out of Africa" theory, homo sapiens left their ancestral home in east Africa around 50,000 years ago, heading north, west and south. Their East Asian descendants eventually crossed from Sibera to Alaska. Thus began human settlement of modern-day North America. But a new study suggests this human odyssey is rather more complex and just as compelling. DNA teased from the bones of a child who lived in Siberia 24,000 years ago shows that the forerunners of Native Americans can also be traced to western Eurasia, or on the western boundaries of Asia. Around 14 to 38 per cent of Native American ancestry today may have originated from humans who came from western Eurasia. AFP